1. Field of the Invention
The invention relates to N-way Wilkinson power dividers for splitting or combining power in a radio frequency circuit.
2. Description of the Related Art
A Wilkinson power divider is a passive electronic device that splits a single RF input signal into two (n=2) or more (n≧3) in-phase output RF signals. Such devices can also be used in the opposite direction to combine multiple in-phase RF signals into a single RF output. The details of design and operation for these devices are well known. Such devices are typically realized using resistors and impedance-transformer sections of RF transmission line (such as coaxial line, microstrip, stripline, etc.) in various configurations.
In many applications, especially for high-volume and low-cost component production, it is desirable to construct Wilkinson power dividers using inexpensive assembly methods and materials such as sputtered, printed or etched circuits on a flat substrate and using planar transmission lines (e.g. microstrip, stripline, etc.). Realizing n-way (where n≧3) Wilkinson power dividers is difficult and expensive, requiring the use of circuits assembled from multiple substrate layers and/or the use of discrete resistors rather than printed or etched resistors. These costs and difficulties have limited the usefulness of N-way Wilkinson power dividers.